ESP8266 Community Forum

As is, this project provides a simple activity sensor using a radar module (or PIR... and notice that the Wemos D1 mini has a useful 5v pin for powering such 5v sensors).

More usefully, a second unit can be used as a networked remote monitor for the first unit.



I have purposely kept the script generic to offer easy networking without need for individual network configurations... so the same script runs both the Sensor and Monitor units (assuming the gpio's are not different).


If both units had sensors they could act as remote monitors for each other.

Multiple remote monitors could be used with a sender if wished.

Multiple senders could also be used, but you'd probably prefer to include facility to send and receive individual unique IDs, which means modifying the code to send and receive your specific ID info. That's easily enough done by appending your own info to the end of
udpwrite udpaddr, udpport, "RemoteAlert" & "Your data here"
in the [TRIGGERED] subroutine, and obviously you then need to extract it in [UDPMSG] and respond as required, so that's down to you.

The project is intended as a useful 'starting point' to be taken further as wished, so hopefully the code should be fairly easy to follow and modify as needed.

Despite the project being based around a Radar module, the minimal hardware for the standalone unit is just any sort of sensor or switch or button for input to trigger alerts, and an LED indicator for showing local alerts.
Be aware that, unlike a PIR, a Radar sensor may detect activity outside of its line of sight, ie: behind walls or other obstacles.

The minmal hardware for a Sender is just a sensor or switch to trigger alerts.

The minimal hardware for a Monitor is just an LED indicator for showing remote alerts.
So it doesn't get much simpler than this, and offers much potential for adding your own knobs and whistles.

The Radar modules default inactivity timeout of 2 secs could be altered by changing one tiny SMD cap... good luck with that!
I would prefer to do it in software: Esp-Basic hardware interrupts are generated when their pin goes Hi or Lo, so basically it's a matter of not declaring a Clear immediately when the Alert pin becomes inactive in [TRIGGERED], but what you do and how you do it (eg: whether using a timer or blocking delay, and whether ignoring subsequent alerts during the extended timeout, etc) is up to you.

Note that interrupt sensorpin, [TRIGGERED] is not declared until the end of [BLINKIP] to ignore any sensor triggers until after the blink IP initialisation has completed.

The blink IP facility allows you to save the same generic script to all units, configure all their SETTINGS the same with appropriate SSID and password and set them all to Autorun, then power them online one by one (even out in the field), watching for their last IP address byte to be blinked out about 30 secs later (after wifi connection). It is assumed you already know your routers subnet address, therefore you just need to know what DHCP node address (the last address byte) it has been allocated so you can connect to it with your browser if needed.

Note that a zero is denoted by 10 LED blinks because none would have been very misleading!


EDIT
A dual-action button-press plug-in has been added at the bottom if anyone wants it.




Dual-Action Button-Press
Just copy the following code over the top of the existing [PRESSED] subroutine in the above code to provide alternative Short (<1sec) or Long (>1sec) button press actions - in this case a Short press 'simulates' a local Alert trigger whereas a Long press Clears accumulated alerts.

How well does this work over all is there sensitivity adjustment for instance if I have a lot of birds in my yard will it spot all the birds all the time ?

Nice thinking on the 10 blinks for zero yes it could be very misleading good simple way to handle that one.

I have often thought of PIR or break beams to know if someone to show up at my house would be pretty cool only issue is to find low powered break beams it seems fairly difficult that stretch any decent distance most of them require some good power.

Good Project though got the wheels turning a bit my next project is going to be a bluetooth boombox for work using some old speakers I have laying around the house should be interesting to see how this goes heh first venture doing so but I scored an amp with bluetooth integrated for fairly cheap well see how it all turns out.

Hello forlotto,
The radar modules I've used are 1 quid each 'throwaway' pcbs which happen to match their 10m advertised range, unlike others, which have had various dissapointing shortcomings.

There is no onboard 'user adjustment' as such, other than changing the value of an smd component to reduce sensitivity.

These radar modules normally have an excellent 8m to 10m full-width detection spread, which can be reduced to a spotlight beam by placing inside a tin can, or increased forwards to about 15m by using a metal reflecter, or incresed to a 40m long by 2m wide beam by using a parabolic dish reflector (eg: an old satellite dish or metalised spotlight/headlamp/torch reflector).

The radar can 'see' through most thin non-metal materials, so it is simply a matter of restricting its sensitivity and/or field of view using eg: metal can or tin-plate for sheilding.
Conversely, you can mount it on a metal parabolic dish to get a longer tighter focused radar beam which could be a better equivalent to a beam-break detector - which are either double-ended (transmitter at one end and receiver at the other) or reflective bounce-back (which halves their range and sensitivity).
Another shortcoming of beam-breaks is they usually have such a tight beam that it is usually possible to either step over or crawl under without triggering, which wouldn't be possible with a focused 2m wide radar beam.

One of the great things about these radar modules is that they are so cheap (£1, free postage) that you can afford to experiment with human proximity detection add-ons for automatic internal lighting and sleep timers etc, so I don't think an inventive person like yourself would be stuck finding applications for them.
For instance... how about a 'magic table' using radar detectors mounted in tin can 'blinkers' underneath the table for sensing your hand movements above, so you could operate the TV or switch different lighting using table-top gestures! You could use the table as a mini menu system, using your left hand to select a left-hand device/function and your right hand to control the selected device. Just some food for thought.

Interesting thoughts indeed.

Flip it around facing into a soup can you get less sensitivity and shorter distance with a more focused beam if I am understanding this right.

Heh as far and inventive it all depends on the day sometimes I have a million ideas and others I am blank I feel this is the normal modus operandi for many of us from my observing of others.

I just spotted the other thread though I am still curious if a yard full of birds would be setting this thing off left and right I would guess it would as birds have signatures on normal radar the type of bird is a small barn swallow we have lots of them so maybe maybe not.

I remember an older thread when you talked of purchasing these things will have to read some more. I'll have to see where you got them from. EDIT FOUND THEM: http://www.ebay.com/itm/122432080819 Whew 10m is quite the spread but if I angle it just right it should kill the neighbors motion from triggering it got to love living right in front of a farm lol lots of motion tractors farm animals farm equipment but the beauty is there is always someone here is the probability of someone trying to break in is small but still would be nice to have often I don't hear the door and we don't have a doorbell either it was a stick on wireless and the sucker blew off in one of the bad storms dunno where it went. I'd say the driveway is about 3 meters wide give or take so if I put it at a forward facing angle on my mailbox I may just have something that would be as good as a break beam or even better as you say.

Thanks for sharing this with our community this is excellent!